Ribosome

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 A ribosome is the particle upon which mRNA from DNA transcription is translated to a polypeptide with a specific amino acid sequence defined by the genetic code. It is comprised of 2 subunits:

30S unit: This is the smaller unit which can be divided into 21 proteins and a 16S RNA molecule

50S unit: This is the larger unit which can be divided into 34 proteins and 2 RNA molecules, 23S and 5S

The 2 units together form the complete ribosome, known as the 70S unit. S refers to the Svedberg unit, which is a measure of rate at which a compound moves when centrifuged.

As ribosomes contain RNA (also referred to as ribosomal RNA-rRNA) and protiens, they are also referred to as ribonucleoproteins. Ribosomes translates mRNA in triplets (codons) by alligning complementary triplets found in tRNA molecules (anticodons). Each tRNA is assigned a specific anticodon and amino acid and therefore translation leads to the formation of a protein by forming peptide bonds between adjacently aligned amino acids.